Printed Circuit Boards (PCB)

Three four-layer FR4 circuit boards with a paste stencil.Professional PCB Supplier

We have supplied our customers with following PCB products since 2011:

  • Advanced Circuit Boards such as large current Power-PCBs or RF/Microwave PCBs.
  • Flexible PCB solutions.
  • Standard FR4 boards.

We have great experience from standard FR4 boards. We have also successfully delivered some of the most difficult to realize special material boards possible. A case example includes production of Rogers multilayer PCBs with 3.5mil minimum track width/track separation. More information on different PCB types, design rules, ordering etc. you get by clicking the buttons shown below.

ORDER / ENQUIRY
DESIGN RULES

Advanced Circuit Boards

The picture shows a special PCB which has a thin slice of Rogers 4003 laminated on top of a thicker carrier FR4 plate.High currents, dense BGA packages and high frequencies often demand a lot of the PCB implementation. For example, we know RF and microwave PCB special challenges very well due to our past Ultrawideband radio, microwave direct-conversion modulator and LNA projects. The latter ended with one US patent.

Case: RF-PCB with Rogers 4350 on top of FR4
Picture shows a 4-layer PCB, which has been manufactured by laminating a thin Rogers high-frequency slice onto a thicker FR4 plate. This combination gives a good 50-Ω match at microwave frequencies with sufficiently narrow tracks. At the same time, use of an FR4 laminate has decreased cost. Sufficiently narrow matched microstrips have been necessary to access all 80-pins of the BGA package.

High Current PCB Solutions

  • High current power PCBs require special thick copper layers to carry the currents without excessive heat.
  • Another key tool is high-Tg board materials, and these can be supplied as multilayer solutions. Stackups with 210um (6OZ) copper with a Tg170 FR4 board material are available, when min. track width and track separation rules are met. Rough guide is to set these at 0.35mm and the minimum via should be 0.5mm.

Professional PCB design help is available by contacting us here.

Flexible PCB

Flexible PCBs increase 3D possibilities

There are many situations when a flexible part between rigid board sections is the ultimate solution. Such cases might be wearable electronics, efficient use of product 3D-space etc.

When the wiring is implemented onto a flexible polyamide section, it will be more dependaple and it will use less space. A flex-rigid board will not be a victim of bad assembly of separate wires. Thus decreased overall cost and increased product reliability can be achieved with this technology.

We can supply you with suitable flex-rigid solutions at the right price. Different color overlays and Legend texts can also be leveraged to increase the final product marketability.

Standard FR4 2L-4L-ML PCBs

LNAFIN electronics-PCB 2L printed circuit board with a blue solder mask and gold finish.A four-layer circuit board described here with a 4L-PCB-sketch

The pictures here stand for the plethora high-quality 100% E-tested circuit boards we have delivered to our customers over the years. Our price-quality ratio is very good and the ordering process is easy. To get a quotation or to order a FR4 PCBs use the order-link at the top of the page and fill in the required data.

Please mention any special structures such as use of blind or buried vias. To give an accurate quotation, we also need to know minimum track width, minimum track separation and minimum via sizes.

We need gerber and drill files to make a binding offer (please pack as .zip, .tgz, tar.gz and attach). Alternatively, we can accept other data formats too (Eagle, KiCad, PADS, OrCad, designspark etc.).

Common PCB surface finishes

Common choices for track surface finish are ROHS HASL or ENIG. The HASL stands for Sn finish according to ROHS regulations, while ENIG is  a gold track finish. The latter is a combination of a thicker Nickel layer covered with a thinner gold layer deposited on the Cu tracks. The gold finish makes for good solderability, neat products and longevity. For wirebondable surface we recommend ENEPIG gold finish.

For solder mask colors  we offer following options: green, blue, red, black and white. These can be combined with different color component prints (silk, legend) to make dramatic good-looking PCBs. For example ENIG tracks, white solder masks and black texts, or ENIG with red solder masks and white legend prints might make a striking effect.

We always treat customer data as confidential.

We have no minimum order amount, but for prototyping purposes we recommend min. three PCBs.

PCB Design rules

Below we have listed our general design rules for successful PCB implementations. These recommendations describe the most important rules for both densely routed demanding and for more inexpensive circuit boards. We have also listed guidelines for thick copper PCB implementations.
Please note that these compact rules cannot 100% guarantee PCB producibility. However, based on our experience these give a good starting point for the designs.

Demanding PCB Design

We have delivered demanding PCBs with min. track widths below 100um, but for high production yield and decreased risk we recommend that you make your densely routed design with these rules:

  • min.track/min. track/track-to-pad distance: 0.1/0.1mm
  • min via/min. via diameter with pad: 0.15/0.45mm.
  • min. laser via/min. via with pad: 0,1/0,35mm.

So laser-drilled vias can have a minimum diameter of 0.1. These rules apply for FR4-boards, for special materials such as Rogers laminates it is always best to contact us first.
Note! We have delivered both FR4 and Rogers boards with even tighter specifications, but such special solutions increase price. These can also be unfit for series production.

Economy PCB Design

  • min.track/min. track/ track-to-pad distance: 0.2/0.2mm
  • min via/min via diameter with pad: 0.3/0.7mm

Note that we can allow reduction of track widths downto 0.15 mm with no problems, and via pads can be made smaller too. Thus via total diamater can sink downto 0.5-0.6 mm from 0.7mm with negligible cost effect.

Thick Copper PCB Design

  • min.track/min. track/ track-to-pad distance: 0.35/0.35mm
  • min via/min via diameter with pad: 0.5/0.9mm

These are tentative guidelines best suited for 210 um copper implementations. When copper thickness changes and PCB area is limited, please ask for additional information.

Special Vias: Micro-Vias / Blind-Buried Vias

Next we will define special vias such as micro, blind or buried vias. These differ from the usual vias w.r.t. the number and location of PCB layers they connect. Micro-vias connect only two topmost or bottom layers, no more. Blind vias connect more layers starting either from TOP or BOTTOM layer, but they never go thgough all of the PCB. The buried via type connects desired layers inside the PCB, but these vias never connect to the outermost layers of the PCB.
Lasered micro-vias can go downto 0.1mm, and the total via dimension can go downto 0.3-0.4mm. However, some inherent limitations come with these tightened “Laser”-rules. For example, some stackup changes might be necessary to make the laser penetrate laminates well enough. Also when using these “Laser”-type design rules for special materials such as Rogers laminates RO4350B, RO6002 etc., we recommend that you contact us for details.

Via-in-PAD Design Recommendation

We can deliver multilayer PCBs with all kinds of special vias such as: blind, buried and microvias. Nevertheless, our general recommendation is that to cut down cost and PCB production time these via types should be avoided. The rationale behind this is simple: PCB layers are today rather cheap. Thus to fit your design in any given PCB dimensions with less cost and less time, we recommend adding layers over special via constructs.

Sometimes adding layers is not possible or sufficient to solve layout design problems. One such case might be when the design includes 0.4-0.5-mm pitch BGA parts. We have successfully solved these cases using via-in-pad structures. The designer can make these vias to have a 0.2-0.3 mm drill size, and these vias can be filled and capped. This way we ensure successful assembly, where no solder will be runnign into the vias. Microvias can similarly be applied with increased but still reasonable cost. After that the design team can apply a blind via structure for example.

Never define multiple different buried and blind vias in the same design. That will make design production time and its cost too high.

Direct Production PCB Data Formats

Gerber 274X, PADS, OrCad, EAGLE, kiCad, DXF, PDF, expressPCB etc.

We can deliver PCBs from almost any data. Past successful PCB deliveries include direct production from data in gerber, PADS, EAGLE, kiCad, DXF, PDF etc. We have also delivered hundreds of PCBs from proprietory CAD tool data formats. For example the free expressPCB program has no open data format output.